1. Field of the Invention
The present invention generally relates to a tube assembly for a burner box of a gas range and, more particularly, to a lightweight tube assembly having a manifold block.
2. Description of Related Art
Gas ranges or stoves typically have a plurality of manually operable valves which respectively regulate the flow of gas through burner tubes to a plurality of burners. The burner tubes are typically connected to the valves and the burners with flare fittings. The valves are typically mounted directly to the side of a manifold tube and spaced apart along the length of the manifold tube. One end of the manifold tube is connected to a gas supply and the other end is flared or sealed so that the manifold tube distributes gas to the valves with an acceptable pressure drop.
These gas distribution assemblies are prone to frequently develop leaks at several different locations. Leaks can develop in the manifold tube due to cracks at the valve connections. Therefore, the manifold tube typically has a relatively large wall thickness and/or is formed from steel. Steel manifold tubes, however, are particularly prone to weld seam leaks, rusting, and bending problems. Leaks also develop due to human error in making the flare fitting connections such as, for example, nut and sleeve problems or loose flares. Leaks can also develop at the flared ends of the tubes which crack over time due to bad tubular seams.
Additionally, these gas distribution systems are heavy because the manifold tubes are relatively large so that they can extend past each of the valves. Typically, the manifold tube extends for nearly the entire width of the gas range. The weight is even greater when the manifold tubes are steel. Furthermore, the manifold tubes may interfere with access to other components of the gas range because they can cannot be easily positioned elsewhere, and usually cannot be split or easily separated. Accordingly, there is a need in the art for an improved gas distribution system for a gas range.
Another problem with the prior art devices is the igniter. Typically spark ignition systems for gas stoves use some type of microswitch mounted on the stems of a gas valve that controls the flow of gas to the burners. When the valve stem is rotated to a predetermined position, contact points on a microswitch touch, closing a circuit and activating the spark module. 115 volts AC is usually present at the microswitch contact points.
A lot of problems have been created with this method. First, AC voltage is present close to the stem where the operators hand is located. Second, the microswitch is subject to damage due to cooking material such as acidic liquids like tomato juice possibly boiling over the pan and flowing onto the cooktop and onto the microswitch which is located underneath a hole created in the cooktop for the stem penetration. Third, microswitches in the small size required are not always that reliable.